It was the year 79 after Christ when the inhabitants of pompeii they watched as hell closed in on them, engulfing them in a wave of toxic gases and lava. The eruption of Vesuvius left thousands of victims, whose rapid death gave rise to a curious phenomenon. The petrified lava around their bodies left holes that, filled with plaster, have made it possible to casts of the exact postures in which were the volcano victims. But that is not the only thing that has been preserved. It seems that the pyroclastic materials released by Vesuvius have made it possible to maintain the DNA of some of those people safe from environmental factors that could degrade it. And he has done it to the point where a team of scientists from the University of Copenhagen and the University of Salento Has got sequence the genome of one of the victims.
The human genome had been previously sequenced. In fact, some gaps that had been inaccessible to sequencing techniques have recently been accessed. However, accessing the DNA of a living or recently deceased individual is not the same as accessing the DNA of someone who died buried by a volcano almost 2,000 years ago.
So far it has been possible to sequence some very short pieces of mitochondrial DNA of humans and animals deceased in Pompeii. It is the first time that it is achieved sequence the entire genome of one of these individuals. And this is great news for two reasons. On the one hand, because it is a clear example of how sequencing techniques have advanced in recent years. On the other, because it provides many interesting facts about how the inhabitants of this city in Italy. It is true that he is just an individual, but he is still a window into the past that is worth taking advantage of.
A nightmare frozen in time
Like any volcano, the writings of the time indicate that Vesuvius began to show signs of activity a few days before the eruption. To see it, many inhabitants of Pompeii fled across the sea. However, there were some who stayed, either because they were confident that it would not be such a big deal or because they did not have the financial resources to do so.
In fact, it is believed that many of those who stayed were slaves that they should take care of their masters’ belongings in their absence. Remains have even been recovered of some who kept rings tied to their ankles.
The eruption surprised some sleeping, while others did take to the streets trying to flee. Everything was very fast and sudden, because they possibly died immediately because of high temperatures, toxic gases and, of course, lava.
Curiously, this volcanic magma at a very high temperature and the pyroclastic materials released have made it possible to preserve a x-ray of pompeii frozen in time. The holes left under the petrified lava have made it possible to make molds of many of the victims, but also of their furniture or animals. We can get an idea of what that Italian city was like. But now, thanks to genome sequencing, we can know much more deeply what its inhabitants were like.
Sequencing the genome of an inhabitant of Pompeii
The sequenced genome belongs to one of two people found in what is known as House of Fabbro or, in Spanish, craftsman’s houseeither. In room 9 there were two individuals. The first was a man who must have been between 35 and 40 years old and about 164 centimeters tall. As for the second, it is a woman over 50 years old, about 153 centimeters tall.
The authors of the study now published in Nature were able to extract and sequence DNA from both. However, they only managed to complete the human genome.
Once the sequence was obtained, they proceeded to compare it with another 1,030 ancient and 471 modern individuals from the same area of Europe. Thus, they saw that their DNA shared the most similarities with modern Central Italians and other individuals who lived in Italy during the Roman Imperial era. However, the analysis of mitochondrial DNAinherited through the mother, and from the Y chromosome, originating from the father, also showed the presence of gene clusters commonly found in those from the island of Sardinia, but not among other individuals who lived in Italy during Roman imperial times. Therefore, there could be a great genetic diversity.
Finally, the presence of bacterial DNA is also striking. Specifically genetic material from Mycobacterium. This is the genus to which the bacterium that causes the disease belongs. tuberculosis, so this individual was possibly sick before the eruption. Maybe that was why he didn’t run away? Or should he rather stay working in the craftsman’s house? We will never know; but at least the DNA provides new clues to one of the most interesting puzzles in history.